tiobench
Quoted 8 lines · Andrew Morton
tiobench sequential read throughput is enormously sensitive to the readahead setting. With the readahead at the default 128k with
blockdev --setra 512 /dev/hdagives very nice throughput. But somehow 2.4.x seems to cheat and seems to do twice the readahead than the setting says, or something.
Bigger readahead helps dbench too.
Readahead in 2.5.x and dbench and tiobench sequential read average throughput on my uniproc ide box was roughly:
kernel readahead dbench tiobench 2.5.0 - 2.5.7 8 8.1 mb/s 9.9 mb/s 2.5.8 - 2.5.10 0 3.5 mb/s 9.9 mb/s 2.5.11 - 2.5.17 256 13 mb/s 10.2 mb/s 2.5.8-akpm 1024 22 mb/s 18.1 mb/s
Bigger readahead appears to lower tiobench sequential read latency a little.
2.4.x showed readahead = 8 for 2.4.3 - 2.4.19-pre8, including aa, ac, jam, mjc, and rmap.
Signature · 1 line
Randy Hron